If the correlation between variables is .70, what percent of the variance is shared variance?

The correlation between variables = r = 0.70
percent of variance which is shared = ?
to find the shared variance we use the following formula,
r² x 100, here r = 0.70 so,
(0.70)² x 100 = 0.49 x 100 = 49%
shared variance is 49% 
100 - 49 = 51%, which is not shared variance